ADVrider

Go Back   ADVrider > Gear > The Garage
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 04-05-2014, 12:39 AM   #1
havoc1 OP
Adventurer
 
Joined: Jan 2013
Location: Pacific Northwet (vic Tacoma)
Oddometer: 32
Pissed How friggin' stupid can I be if I can't bleed front brake on my Suzuki Cavalcade?!

Fellow inmates,
I accept that I am an idiot. I readily embrace it, in the odd chance that doing so moves the collective to take pity upon me and offer up a solution to my mouth-breathing stupidity that does not include fire. (That's my solution, so it's already taken. You'll have to offer something different.)

1986 Suzuki Cavalcade...aka "Wynona" the Big, Brown Beater. Prepping for a sale because there's no more room at the inn for a two-wheeled yacht. Sale is in 12 hours...if I can get my crap together. Old lines for the front brake were flexing and squishy, so I installed new braided stainless lines. Rather than pull it apart and find it to be junk, I replaced the master cylinder too. So far, no big deal, right?

I can NOT build pressure in the lines. I have put almost a quart of fluid through this thing.

1. I've attempted a vacuum bleed. Reservoir level comes down, but brakes never firm up. Pump a dozen times on the brake lever and hold, get vacuum with the pump, crack the bleeder, suck some out, close bleeder, repeat.
2. Next, I found a big-ass syringe and used it to pump fluid in from the caliper bleeders in order to force air up and out. The reservoir fills (had to suck some out twice now), but again, the brake never firms up.
3. I stumbled on directions at Cavalcade.com which mention that the master cylinder is canted the wrong way on the bar and collects bubbles. OK, I unclamped the entire assembly, tilted it so bubbles could escape, and started pumping on the brake handle. Well, I got streams of itty-bitty bubbles the first few times, and then a couple of larger bubbles, so I was really excited. I rejoiced. I celebrated. I saw no discernible difference in pulling the brake.
4. I tried to vacuum bleed again now that the master cylinder is bled. No improvement.


I swear it's like the brake is pushing absolutely nothing, even though I can see the fluid flowing in and out of the master cylinder when I look closely while squeezing. Trying a classic bleed (squeeze, hold, crack, tighten, repeat) doesn't work either because I can't get enough pressure to do anything. No leaks from the calipers that I can ID.

What the hell is going on here? Suggestions? What the actual f*ck?! Some old dude is coming to look at the bike Saturday at noon and I'm completely stumped by a job that's beginner at best.
havoc1 is offline   Reply With Quote
Old 04-05-2014, 04:36 AM   #2
radianrider
Adventurer wanna'be
 
radianrider's Avatar
 
Joined: Aug 2006
Location: Avon, IN Not so much Motorcycle Heaven
Oddometer: 403
Had a similar issue with my old Suzuki last summer. Fought it for months. A fellow ADV'er figured out that the caliper piston was hung up. Might checked to make sure the pistons are retracting properly.
radianrider is online now   Reply With Quote
Old 04-05-2014, 06:40 AM   #3
ragtoplvr
Beastly Adventurer
 
Joined: Oct 2007
Location: S. W. Mssouri
Oddometer: 5,384
Pump it up as hard as you can get it. Rubber band the lever down. Then tap all the lines. The now smaller bubble should move up so it can be expelled.

Very small squeezes, just cover and un cover the little bleed hole sometimes help more than hard ones.

Rod
ragtoplvr is offline   Reply With Quote
Old 04-05-2014, 06:47 AM   #4
orangebear
Beastly Adventurer
 
orangebear's Avatar
 
Joined: Aug 2010
Location: dumfrie scotland
Oddometer: 1,196
i hate doing brake bleeding as its hard to get it to work right so i be taking the bike to a garage when it needs done.
__________________
bmw r100gs i ride it all year round
bmw r100/7 x2 sold
road legal stomp pitbike sold
Klr650c the 1 I should not of wasted my money on
Honda xl125rc powered by a cg125 block fun wee bike
orangebear is offline   Reply With Quote
Old 04-05-2014, 07:30 AM   #5
kraven
Hegelian Scum
 
kraven's Avatar
 
Joined: Jul 2005
Location: Asheville NC
Oddometer: 4,431
Check the caliper seals and the master cylinder seals.
__________________
"If they would have made this 15 years ago... Well, I would have killed myself to death actually. But what fun while it lasted." -lagcam
kraven is online now   Reply With Quote
Old 04-05-2014, 08:58 AM   #6
havoc1 OP
Adventurer
 
Joined: Jan 2013
Location: Pacific Northwet (vic Tacoma)
Oddometer: 32
Quote:
Originally Posted by ragtoplvr View Post
Pump it up as hard as you can get it. Rubber band the lever down. Then tap all the lines. The now smaller bubble should move up so it can be expelled.

Very small squeezes, just cover and un cover the little bleed hole sometimes help more than hard ones.
Worth a shot again--I hadn't thought about reducing the bubble size so they'll travel up, but I guess that's the old wisdom about leaving the lever tied to the grip overnight.

Quote:
Originally Posted by kraven View Post
Check the caliper seals and the master cylinder seals.
I know the master cylinder is good, since I just replaced it and it had good friction/feel. At least as good as the old one. ...right?

I'll go yank the calipers. But they worked just fine before. Is that any indicator?
havoc1 is offline   Reply With Quote
Old 04-05-2014, 10:59 AM   #7
havoc1 OP
Adventurer
 
Joined: Jan 2013
Location: Pacific Northwet (vic Tacoma)
Oddometer: 32
Sonofabitch. Zero success. Not a single bubble released, and I just got done attempting a reverse-bleed again. I'm out of brake fluid and will have to get more, so it looks like sale is off for today and I'm going to tear the calipers and the entire system apart.

Popped the calipers off of each side and levered between the pads a bit with a wooden shim. They seemed to retract, which would apparently be a sign that the pistons are not stuck or seized. Of course, they worked fine a few days ago with the old lines, so I sort of expected that.

If there's no air in the lines, no air in the master cylinder that I can find...where else could I be going wrong?
havoc1 is offline   Reply With Quote
Old 04-05-2014, 11:50 AM   #8
vicster
Studly Adventurer
 
Joined: Aug 2007
Oddometer: 798
Don't let it get you down, I've heard of, and had, similar experiences myself. Looks so easy on paper, right?
At this point I think I'd be tempted to try it with the original master cylinder. You never know...
vicster is offline   Reply With Quote
Old 04-05-2014, 12:17 PM   #9
kraven
Hegelian Scum
 
kraven's Avatar
 
Joined: Jul 2005
Location: Asheville NC
Oddometer: 4,431
I've gotten new/reman master cylinders that didn't work out of the box and had to be exchanged.

Pull the pads and use a clamp to seat the pistons, then work the lever to see if they move. As long as they don't pop out everything is okay. Give the lever a squeeze and see if they move.
__________________
"If they would have made this 15 years ago... Well, I would have killed myself to death actually. But what fun while it lasted." -lagcam
kraven is online now   Reply With Quote
Old 04-05-2014, 12:57 PM   #10
havoc1 OP
Adventurer
 
Joined: Jan 2013
Location: Pacific Northwet (vic Tacoma)
Oddometer: 32
Thumbs down Here's a video of the master cylinder

https://youtu.be/RqpRrZQOZ4I



Ah, video documentation of my shortcomings as a man and mechanic.

Buyer came by and wants it...aslong as he can ride it. Geez, some people are so demanding... ;-)
Gonna have a few thinkin' drinks and try the old piston before I tear the brakes apart.


havoc1 screwed with this post 04-05-2014 at 01:09 PM Reason: fat fingers
havoc1 is offline   Reply With Quote
Old 04-05-2014, 07:41 PM   #11
luftkoph
Adventurer
 
Joined: Jan 2008
Location: U.P. mich
Oddometer: 32
Since you have tried everything,a palm sander minus the sand paper,hold it against calipers and banjo bolts.
luftkoph is offline   Reply With Quote
Old 04-05-2014, 07:56 PM   #12
_cy_
Beastly Adventurer
 
Joined: Sep 2011
Location: Tulsa, Oklahoma
Oddometer: 4,460
up next is to reverse bleed ... push fluid up from bottom. a phoenix brake tool is nice .. a 50cc syringe is not as handy but does the job.
make sure master cylinder is the highest point with no lines above BMC

sometime depressing brake lever partially in overnight does the trick. use a bungee cord or nylon strap to hold down lever.



here's mine
_cy_ is online now   Reply With Quote
Old 04-05-2014, 08:06 PM   #13
aterry1067
Gnarly Adventurer
 
aterry1067's Avatar
 
Joined: Dec 2010
Location: Southern Maryland
Oddometer: 230
Sounds like the fluid is bypassing somewhere. First suspect is the new master cylinder. You could tear the master cylinder apart and have a look at the rubber bits in there, especially around the piston. As suggested earlier, try it with the old MC installed. One thing I have been guilty of more than once is while vacuum bleeding, sucking the reservoir dry and sucking air into the line. Then I get to start the whole process over. If you have pulled enough fluid through the lines to replace all the fluid (and you haven't introduced more air by sucking the reservoir dry) then something else must be going on. Either a loose connection that is allowing air to enter (but you should see it leak when it pressurizes), or more likely it's bypassing in your master cylinder.
aterry1067 is offline   Reply With Quote
Old 04-05-2014, 09:25 PM   #14
JerryH
Vintage Rider
 
JerryH's Avatar
 
Joined: Jul 2009
Location: Chandler, AZ
Oddometer: 3,998
I used SpeedBleeders on my Goldwings http://www.speedbleeder.com/ they had linked brakes which were almost impossible to bleed. They worked great. But on the '85, I first had to rebuild all 3 calipers and both master cylinders. The primary seals were shot in the master cylinders, so they were not pumping any fluid. A plugged brake line, caliper, or a blocked return passage in the master cylinder will also prevent them form working. Brakes are simple, but absolutely everything has to be perfect for them to work right.
__________________
2002 Vulcan 750, 2013 Royal Enfield B5
2001 XT225, 2009 Genuine Stella
2012 Zuma 125, 1980 Puch moped
JerryH is online now   Reply With Quote
Old 04-06-2014, 05:19 AM   #15
GB
Mod Squad
 
GB's Avatar
 
Joined: Aug 2002
Location: Toronto, ON
Oddometer: 55,049
Let's try this in the Garage, where the master techs will chime in.
__________________
ADV decals, patches & flag? Here
GB is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 06:12 PM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014